The lights are back on for Iylene Becker, a 50-year-old Silver Spring woman who breathes at night through an oxygen concentrator system and ran into problems when Sunday's thunderstorm cut power to her home.

Her mother, Adele Becker, said the electricity was up and running at 6 p.m. Tuesday. It was also working on the rest of the block, she said.

Adele Becker said Pepco representatives told her three times last year that the company does not keep a list of customers with special medical needs. Ed Sandel, a longtime friend of the Beckers and a Rockville resident, said Wednesday he was also told that no such list existed when he called Pepco's emergency line this week.

But Pepco says its emergency notification program, which serves 1,314 customers, has existed for more than 15 years.

Adele Becker said she plans to call Pepco again soon and ask about the program. For now, she is happy that her daughter -- who had her windpipe surgically opened last year -- is able to sleep using her electric oxygen concentrator system rather than the liquid oxygen used in emergencies.

After the electricity failed late Sunday afternoon, Adele Becker bought 175 pounds of liquid oxygen, which does not require electricity. Her daughter used liquid oxygen until power was restored.

"As long as we don't have to worry about what's going on at night, that's a good thing," Becker said.